\[2 \cdot \left(\left(1 \cdot \frac{1}{9} + \frac{1}{9} \cdot \frac{1}{9}\right) + \frac{1}{9} \cdot 1\right)\]

2 \cdot \left(\left(1 \cdot \frac{1}{9} + \frac{1}{9} \cdot \frac{1}{9}\right) + \frac{1}{9} \cdot 1\right)

double f() {
        double r41807 = 2.0;
        double r41808 = 1.0;
        double r41809 = 9.0;
        double r41810 = r41808 / r41809;
        double r41811 = r41808 * r41810;
        double r41812 = r41810 * r41810;
        double r41813 = r41811 + r41812;
        double r41814 = r41810 * r41808;
        double r41815 = r41813 + r41814;
        double r41816 = r41807 * r41815;
        return r41816;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019199 
(FPCore ()
  :name "Rectangular parallelepiped of dimension a×b×c"

  :herbie-target
  (+ (+ (* (* (/ 1.0 9.0) 1.0) 2.0) (* 2.0 (* (/ 1.0 9.0) (/ 1.0 9.0)))) (* 2.0 (* 1.0 (/ 1.0 9.0))))

  (* 2.0 (+ (+ (* 1.0 (/ 1.0 9.0)) (* (/ 1.0 9.0) (/ 1.0 9.0))) (* (/ 1.0 9.0) 1.0))))

Backtrace

car: contract violation expected: pair? given: '()		L	C
loop	/data/pavpan/nightlies/herbie/master/src/points.rkt	122	4
prepare-points	/data/pavpan/nightlies/herbie/master/src/points.rkt	146	0
run-improve47	/data/pavpan/nightlies/herbie/master/src/mainloop.rkt	342	0
(unnamed)	/opt/racket-7.2/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.2/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.2/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.2/collects/racket/private/more-scheme.rkt	261	28